Speech recognition technique is a technique for recognizing a speech signal input by a user or the like as a signal corresponding to a predetermined language. For example, speech recognition technology may be used for controlling an operation of a predetermined electronic device, such as voice recognizing navigation system, a mobile phone, and a TV.
In order to improve speech recognition rate, a speech enhancement technique, which is a technique for extracting a pure speech signal by removing noise mixed in an input speech signal, may be used. Examples of techniques related to speech enhancement may include beam-forming that focuses a speech from a particular direction and removes ambient noise and noise suppression that removes static noise.